What is a web cookie?

A web cookie is defined as a small text file placed on a computer by a web server. When a user visits a website, that site can create a cookie containing information such as user preferences, session identifiers, and tracking data. This cookie is then stored locally on the user's device, allowing the website to remember the user's actions or preferences over time, even across multiple visits.

Cookies are essential for personalizing user experiences on the web. For instance, they enable e-commerce sites to keep track of items in a shopping cart as users browse the site. They also play a crucial role in authentication, allowing users to remain logged in as they navigate different pages.

The other options do not accurately capture the nature of a web cookie. Since cookies are indeed stored locally on the user's device rather than a remote server, that option does not describe their function. Additionally, cookies are not specifically commands to control server behavior; rather, they are data stored on the client side. Finally, while cookies can be used in secure environments, they are not limited to such usages. They are utilized broadly across various types of web interactions.